1. Field of the Invention
This invention relates to beds and, more particularly, to beds of the so-called "hospital" type, being particularly designed for use in hospitals and nursing homes or for residential use with patients who are possibly ambulatory but are too weak or incapacitated to get into or out of bed without assistance.
2. Description of the Prior Art
Bed patients, whether in a hospital or nursing home or even at home, are not infrequently in a physical condition where they can move about by themselves--for example, to go to the bathroom or take short walks, with or without assistance--but lack the strength to lift themselves out of bed unaided. Not infrequently, such patients are obese or at least represent a nearly deadweight load of 200 to 300 pounds. Attempting to assist such a patient to get out of bed and assume a standing position requires substantial strength on the part of an assisting nurse or orderly. Such personnel are often faced with the problem of over-exerting themselves in assisting such a patient, and backstrain is a common complaint among nurses for this reason. An alternative is for the nurse to call upon stronger male orderlies to help, but they may not be readily available at the very point in time when the patient needs to get out of bed to go to the bathroom.
There are various examples in the known prior art of attempts to solve the problem of repositioning patients in a bed or on some other supporting surface and in transferring patients between a bed and a cart or gurney for transporting to some other area of the patient care facility, as for the taking of X-rays, for surgery, etc.
U.S. Pat. No. 3,810,263 of Taylor et al is directed to a medical examining table which includes a conveyor belt for moving a patient longitudinally of the table to facilitate locating the patient in various examining positions as selected by the doctor. The table includes a hinged portion which can be raised to help the patient get off the table and also discloses a mechanism for feeding paper or other sheet material along the table, as is customary to provide a clean resting surface for each successive patient.
U.S. Pat. Nos. 3,854,152 of Chez and 3,871,036 of Attenburrow disclose apparatus for transferring patients between a bed and an adjacent cart or gurney. A movable belt is employed to slide under the patient and effect the transfer operation. The Chez patent describes a pair of endless belts which gently grasp the patient and transfer the patient to an upper belt.
U.S. Pat. No. 3,886,610 of Sheldon discloses a hospital bed incorporating a plurality of individual laterally-directed bolsters connected to a longitudinal drive belt and used to reposition a seriously ill patient in an intensive care unit longitudinally of the bed in which the head section is cranked up to raise the patient's head and shoulders, the purpose being to counteract the tendency of the patient to gradually slide downwardly toward the foot of the bed because of the elevated position of the upper part of the body. As the bolsters are moved toward the head of the bed, the leading bolster can be removed and placed at the foot to maintain the extent of the mattress portion as the patient gradually slides relative to the bolsters.
U.S. Pat. No. 3,936,893 of Anderson et al discloses a convertible wheel chair and bed with an elevator mechanism for raising and lowering the support surface between the upper level desired for a hospital bed and the lower level desired for wheel chair height.
The known prior art does not address itself to applicant's concept of converting a hospital bed to an armchair by raising the back portion and translating the mattress toward the foot of the bed to form a structure which supports a patient in a sitting position with feet on the floor and, further, to elevate the thus-formed chair to assist the patient in gradually assuming a standing position without the need for assistance from attending personnel.